Water heater



F. GARVIN Feb. 2o, 1940.

WATER HEATER Filed March 2, 1938 l llllllllllll/ll.

INVENTOR) N' UNITED STAT Patenfed Feb. 2o, 1940 .EST

c WATER HEATER c Frank Garvin, Pittsburgh, Pa. Application MarchZ,1938,` Serial No. `193,461

` 2 Claims. (Cl. 1722*,23)

'Ifhis invention relates to liquid heaters, Vparticularly waterheaters,and one of its main objects is toprovide a heater having a high degreeof eiiciency of heat transfer from a burning gas to a liquid.

Another object of theinventionis to provide a water heater `which is ofan uncomplicated, inexpensive construction, which has a long life, and`requires only `a minimum amount `of maintenancework thereon. l

` Otherfobjects willbecome apparent whenthe following detaileddescription is read in con junction with the accompanying drawing, in

which Fig. 1 is an elevation, partly in section,`

`of the preferred embodiment of the invention, showing it connected to astorage tank; Fig. 2 is an enlarged longitudinal section taken on lineII-.II `of Fig. 1; Fig. Sis a transverse section on line III-III ofFig.2; and Fig. 4 is a perspective View` of the burner block `of theheater shown in Figs. 2 and 3. p

The liquid heater constructedaccording to this invention` ordinarilycomprises a metallicblock which is provided with a gas chamber therein,so that the block serves as a gas burner. Numerous small ducts areformed in the block and they extend radially of the block from the gaschamber to the periphery of `the block to lead gas to the atmosphere,where `itburns on the surface of the block, surrounding it with a sheetof iiame that heats the block to a high temperature. A bore relativelysmall in comparison with the` cross sectional area of `the block forms awater chamber extending `longitudinally through the 35 burner block.`This is adapted to expose water to l `the heat contained in the block,andthe comparatively small volume of water exposed tothe relativelylarge mass of metal of the metallic burner greatly increases the`efficiency of heat transfer to the water. Also, the small volume ofwater exposed to absorb heat from the burner Gblockat any given instant,gives a rapid increaseA in its temperature.` c

A tubular extension is carried by the top of the burner block and isadapted to expose a small volume of `water therein to the heated gasesrising from the burner block. `This increases the exposure of thewaterto heat from the burner before flowing from vthe heater.

Referring now to the drawing, a storage tank l is shown mounted in avertical position on a suitable base 2. c c tioned, metallic burnerblock 3 is mounted adjacent the tank l and has an eccentrically boredlongitudinal gas chamber 4 formed therein.

. over the blocks surface and thereby permit gas burner block to permitcirculation of Water there- A cylindrical, vertically posi-v to asuitable valve 8 which ispositioned adjacent radially bored ducts 5,which are formed in the block and which extend from the gas `chamber tothe periphery of the block. Preferably the axis of the block 3 isincluded in the gas chamber 4, but the gaschamber ispositioned eccenmtric with relation thereto. The ducts 5 normally are positioned `in a`series of spaced planes, as

seen in Fig. 1, and may be radially directed relative to the` block 3 todistribute them equally to burn immediately adjacent all surfaces of theblock, and the flame to be uniformly distributed thereover.`'Ilieexposed ends of the ducts 5 are flared, or reamed, as shown, so asto hold the` flame close to thewblock. A` plug lla is removably securedin the upper end'of the `block 3 to close thegas chamber 4 and seal thegas therein. y

Alongitudinally bored water chamber `(i extends through the block 3,positioned so that it does not connect with any of the ducts 5. Neces-25 sarily, any water in the chamber 6 contacts the block` 3, throughitslength and readily absorbs heattherefrom. This action is expediteddue. to

the small amount of water present in the block at any given instant. Inthe embodiment lof the invention shown in the drawings, the ratioof thevolume of metal of the block to the volume of water in the block isroughly 20 to 1 and,

while I do not `Wish to be limited thereto, this ratio has givenexcellent results. Figs. 2 and 4 show the relatively small volume of thewater chamber B in relationvto the large volume of metal.` forming` the'block 3, and this is a primary feature of the invention anddifferentiates the burner from all burners now known to me. Fig. 2 alsoshows the superposed casing formed by extension member I2, havingannular outer walls I2b and inner walls |20.I The annular `chamber soformed is connected with the bore 6 in the between. It will be seen thatthis superposed casing forms a thin annular water chamber of smallvolumetric content and comparatively large surface exposure of the watertherein heat conducted through the thin outer wall 12b of the casing.

To provide the block 3 with gas, a pipe 'l extends from a source of gassupply, not shown,

heater.

the block 3.' The valve 8 controls the flow of gases to the block and isconnected to the gas chamber by an aerator 9. The aerator 9 is ofstandard construction, havingholes I0 formed therein which are providedwith adjustable covers II to vary the amount of air to be mixed with thegas flowing through the aerator. Thus a proper combustible mixture canbe made prior to introducing the gas into `the block. After the preparedmixture of gas reaches the gas chamber il, entering through lateral boreI9, it can flow therefrom only through the ducts 5. It is then. burnedimmediately adjacent and surrounding the surface of the block. A gasdiffuser, or spreader, may be placed inthe gas chamber adjacent the boreI9, if desired. The block 3 is normally positioned with its axisextending vertically, for this permits the hot gases produced at thelower end of the block to flow along'` its surface as they rise. Heat isabsorbed by the block from'the ame surrounding it. The burning gasesfunction tovheat the `block 3 to a higher temperature. The relativelylarge volume of the block facilitates the transfer of heat ltotherelatively small volume of liquid contained in the water chamber 6. l

A tubular extension member I2 is secured to the top of the burner blockby any suitable means, such as a threaded union Iza, and it is providedwith a chamber i3 intermediate its inner and outer walls, as shown inFig. 2. A tubular member 12b forms the outer wall of the tubularextension member l2 and is secured to a tubular member H20 forming theinner wall ofthe extension member by a threaded sleeve IZd. The tubularextension member connects with the upper end` of the water chamber 6.and is constructed and arranged to receive Water in the chamber I3whereby the water `is exposed to the hot gases V rising'upwardly from'the burner block 3. This provides additional opportunity for heattransfer to the water'prior to its removal from the A baille plate I4having a plurality of holes therein is preferably formed integral withthetubular member |21) to divert water iowing frombore 6 into theheating chamber I3. Washn ers 22 and 23 are positioned at the connectionbetween the tubular members I2b and I2cy and the joint between thetubular extension member I2 and the block 3, as shown. '1

, A pipe l5 is secured to the upper end of the t tubular extensionmember I2 and extends to the upper lportion of the storage tank I'. Thispermits the water heated in the burner block to rise and flow therefromto the upper portion of the'storage tank. Water circulates through thetank and'back to the burner by pipe I8,in well knownmanner. The pipe I8is` connected to the block 3 by a coupling member 20 which providesa-preheating chamber 2| at the bottom of the block. This permits waterto contact the bottom of the block and receive heat therefrom prior toits entrance into the block. 'A washer 24 should be placed between theblock 3 and the coupling member. to provide a water-tight joint..

A suitable jacket I6 is positioned around, and encloses theblock 3` andexhausts the gases produced by combustionthrough a flue I'I.

.Practice of `the invention increases the eifr- 'ciency of heat.transfer between the burningI gas and the liquid to be heated for thelarge volume .of metal in the burner relative to the amount of liquidtherein produces this highly desirable result. 'It will be seen that theshape ofthe burner, or heater, block may vary Widelywithout departingfrom the inventive concept( According to the provisions vof the patent yand described what I now consider to represent its best embodiment.However, vI desire to have it understood that,y within the scope of theappended claims,v the invention maybe practiced otherwise than asspecilically illustrated and described.

Iclaim: l

1. A waterv heater' adapted for usey with a storage tank, comprising avertically positioned metallic block having a gas` chamber `formedtherein and a plurality of bores leading' from the chamber to theperiphery of the block, block also having a relatively smallwater-receiving chamber extending longitudinally therethrough, means forleading combustible gas to said gas chamber, and a tubular extensionmember secured to the 4top of saidblock and connected to saidWater-receiving chamber, saidtubular extension-member being constructedand arranged to expose water to gases of combustion rising uptivelysmallWater chamber extending longitudinally through the block, and meanssecured .to

comprising inner and outer Walls sospaced as v to provi-de `an annularwater-containing space of small -volumeand relatively large surfaceexposure to external heat. n

p LEFRANKGARVIN.

